Highway slotting device

ABSTRACT

There is disclosed herein an elongated member disposed transversely of a lane of newly poured concrete and dragged forwardly lengthwise of the lane while in such transverse position, the elongated member having a multiplicity of closely spaced, parallel, flexible rods projecting rearwardly at a slight downward angle and pressing resiliently into the plastic concrete and progressively forming slots therein, the elongated member also having adjustable counterweights projecting above the rods and sustaining a downward pressure on the rods.

United States Patent 11 1 3,703,857 MacKinnon 1 Nov. 28, 1972 [s41 HIGHWAY SLO'ITING DEVICE 3,596,578 8/1971 Jones ..94/45 R 3,605,579 9/1971 Heltzel ..94/45 R nnon, N [72] Invenmr' il' i 22 ew 3,516,339 6/1970 Perkins ..94/45 [73] Assignee: The W. M. Brode Company, Newcomerstown, Ohio [22] Filed: July 2, 1971 [21] Appl. No.: 159,152

[52] US. Cl 94/45 [51] Int. Cl ..E0lc 19/22 [58] Field of Search ..94/44, 45

[56] References Cited UNITED STATES PATENTS 774,005 1 l/1904 Thies ..94/45 R 2,746,366 5/1956 Reed ..94/45 R 2,965,987 12/1960 Graves ..94/45 R X 3,453,988 7/1969 Trent ..94/45 R X Primary Examiner-Nile C. Byers, Jr. Attorney-J. H. Slough [57] ABSTRACT 15 Claims, 7 Drawing Figures PATENTEBnnv 28 L972 3. 703,85 7

SHEET 2 OF 2 1/. h fiUGl-l A TT'OR NEY HIGHWAY SLO'I'I'ING DEVICE This invention relates to a tool for impressing slots or grooves in newly poured concrete and is particularly adapted for use in impressing slots or grooves in highway, street, and airport runway pavement.

A common hazard of high-speed travel on wet pavement is the effect known as hydroplaning in which the tires tend to skim the surface of the water thereby greatly reducing friction against the road. Braking effect and skid control are substantially eliminated under these circumstances.

One effective method of reducing hydroplaning is to provide parallel, narrow, closely spaced slots or grooves in the pavement running either longitudinally or transversely of the direction of travel. The grooves provide low-pressure escape routes for the water which thereby has less tendency to build up under the speeding tires. 7

The usual method of providing the slots is by cutting with a diamond cutter. The concrete is first allowed to harden, and /8 inch slots are then cut to the desired depth of about A; inch on approximately 34 inch centers. Electronic sensors and feeler gauges are used to automatically guide the machine and readjust the blades to the required depth.

Cutting the slots or grooves in the pavement is slow and requires cumbersome, complicated machines. It is not possible by means of known grooving machines to slot the entire width of a highway lane at one time, it being necessary for the groover to make numerous passes in the same lane. Additionally, cutting causes rupture of the concrete surface membrane which allows salt to attack the aggregates of the concrete and cut grooves have sharp squared edges which are subject to chipping and fracture.

The present invention comprises an elongated member or holder having a multiplicity of closely spaced, parallel, thin flexible rods projecting outwardly along one longitudinal edge thereof and means supporting adjustable counterweights extending above the rods. The elongated holder is adapted to be dragged or otherwise propelled across newly poured concrete with the longitudinal dimension thereof disposed transverse to the direction of travel whereby one longitudinal edge comprises a leading edge and the opposite longitudinal edge comprises the trailing edge from the latter of which the flexible rods project rearwardly. The counterweights tend to rotate the holder whereby the thin, flexible rods are pressed flatwise into the surface of the wet concrete, a substantial portion of each rod being drawn through the plastic material and progressively pressing a slot therein. The counterweights are adjustable for providing more or less pressure on the rods whereby to determine the depth of the slots.

The primary object of this invention is to provide a simplified, improved tool for making parallel, elongated slots in pavement surface for the reduction of hydroplaning.

Another object of the invention is to provide such a tool which forms slots much more quickly over a given area than known tools or machines.

Still another object of the invention is to provide a tool of the above type which can provide slots the full width of a highway lane in one pass.

Yet another object of the invention is to provide a slot making tool which eliminates the need for complicated machines or sensors.

A further object of the invention is to provide a tool for making slots in paving concrete in such manner as to maintain the surface membrane of the concrete intact.

A still further object of the invention is to provide a slotting tool which will leave rounded edges on the sides of the slots at the surface level of the pavement.

Other objects of the invention and the invention itself will be understood from the following description thereofand the accompanying drawings, in which said drawings:

FIG. 1 is a rear perspective view of a truck having a laterally projecting boom dragging the hydroplane slot impressing tool of this invention over a lane of wet cement;

FIG. 2 is an enlarged top plan view of the left-hand end portion ofthe impressing tool as seen in FIG. 1;

FIG. 3 is an elevational view of the impressing tool as seen from the left-hand side of FIG. 2;

FIG. 4 is a further enlarged section taken substantially along the line 44 of FIG. 2;

FIG. 5 is a vertical section taken along the line 55 of FIG. 3;

FIG. 6 is a fragmentary section taken along the line 66 of FIG. 2 and FIG. 7 is a transverse section taken substantially along the line 7-7 of FIG. 1.

Referring now to the drawings in all of which like parts are designated by like reference numerals, and referring particularly to FIG. 1, the highway slot impressing tool of this invention is generally indicated at 10 and is shown disposed upon and secured to one end of a wide fabric sheet 11 which may be any suitable tough cloth material, such as burlap. The forward end of the sheet 11 is shown connected to a boom 12 which projects laterally from the back end of a road vehicle such as a truck 13 shown in dotted lines. The boom 12 projects laterally transversely of the direction of travel of the truck sufficiently to bridge a lane 14 of newly poured concrete, the outer end of said boom as shown being provided with a wheel 15 and an angled brace 16, the latter being connected between the outer end of the boom and a forwardly disposed point 17 on the truck 13. The forward end of the fabric sheet 1 l is secured to the boom 12 substantially along its complete forward edge by any suitable means such as a hold down strip 18 secured by nails 19. The sheet 1 l is secured all along its rearwardly directed end edge to the bottom of the tool 10 by any suitable means such as nails 20 (FIGS. 3 and 5).

It will be understood that the above described means for sliding or dragging the tool 10 across the surface of newly poured concrete is given by way of example only, and other means may be used whereby said tool is either dragged lengthwise or across a lane, runway,.or slab of concrete to impress slots therein. The present example is specifically adapted for impressing slots over the entire width of a highway land of newly poured concrete, the arrangement being such that a vehicle can be propelled parallel with the lane with a pulling means such as the boom 12 projecting out over the lane.

Referring now particularly to FIGS. 2-6, the slot impressing tool 10 comprises an elongated holder 25 made up of a base 26 and a clamping portion 27. The holder 25 may be made of wood and, in fact, may be cut from a standard piece of 2 6 lumber. The 2X6 is so cut as to provide the base 26 with a rearwardly jutting shelf or lip 28 having an upper surface 29 which slants rearwardly and downwardly at an angle, the angle being substantially 12 as herein shown. The clamping portion 27 has a similarly angled lower surface 31. Adjacent to the forward or inner end of the upper surface 29, the base 26 is provided with an upwardly and forwardly slanting step 30. It will be obvious that if a 2X6 is cut longitudinally along the plane defined by the upper surface 29 .and the step 30 to sufficient depth that the two cuts meet, a complementary portion may be removed and used for the clamping portion 27.

The clamping portion 27 is secured to the base 26 by suitable tightening means such as elongated bolts 33 and nuts 34. The bolts 33 project horizontally through suitably aligned apertures 26a and 27a extending coaxially through the base 26 and the clamping portion 27, respectively, in the direction of the width of said base.

The lower surface 31 of the clamping portion 27 is provided with a multiplicity of parallel grooves 36 disposed at right angles with respect to the longer dimension of said clamping member. Each groove is adapted to nest over but not completely encase the forwardly directed end of a thin, moderately flexible plastic rod 37 preferably having a diameter of substantially /8 inch. It will be readily seen that by tightening the nuts 34 on the bolts 33, the clamping portion 27 is urged toward the step 30 of the base 26 whereby the forward ends of the rods 37 are clamped tightly between the slanted surfaces 29 and 31 and are held against lateral displacement by the rooves 36. As particularly'shown in FIGS. 1-3 and FIG. 6, the clamping portion 27 is held against upwardly displacement by meansof a plurality of blocks 38 which are rigidly secured in any suitable manner to the upper surface of the base 26 forwardly of the step 30 and project rearwardly over said clamping portion. Thus the rods are tightly held in use and readily removable and replaceable by loosening the clamping portion 27.

As particularly shown in FIG. 6, the blocks 38 also serve to provide substantially thickened portions along the holder 25 for mounting upwardly and rearwardly slanting supports, each comprising a rod 40 and a horizontal bolt 42; Each rod 40 is tightly secured within an angled socket 41 which extends downwardly through the associated block 38 and into the base 26. As herein disclosed, the blocks 38 are made of wood and the rods 40 are of steel bar stock having a Y4 inch diameter. The rods 40 may also be made of steel bolts of substantially the same size. The'upper ends of the rods 40 are provided with elongated, rearwardly cantilevered i inch bolts 42, which are threaded throughout the length thereof to engage internally threaded counterweights 43. The forwardly directed ends of the threaded bolts 42 are welded to the upper ends of the rods 40, and the said bolts 42 are disposed substantially parallel with the plane of the base 26 whereby said counterweights are disposed substantially above the rods 37. It will be readily seen that when the base 26 is disposed flatwise upon the upper surface of newly poured or wet concrete, the counterweights 43 will tend to cause the holder 25 to rotate in the clockwise direction as illustrated in FIGS. 3, 4 and 6, the leading edge tending to tilt upwardly and the trailing edge downwardly. This rotation will be resisted by the multiplicity of flexible rods 37 which will thereby be pressed sidewise downwardly into the soft concrete.

The pressure on the rods 37 can be varied by rotating the counterweights 43 on the bolts 42 to move them either rearwardly or forwardly to increase or decrease the lever arm thereof, respectively. The setting of the counterweights will depend upon the depth of penetration desired, the temperature, and the viscosity of the wet cement or concrete. As herein disclosed, the slots are intended to conform to the present standards of cut slots or grooves, the same being substantially 4; inch deep by A; inch wide spaced on 36 inch centers.

FIG. 7 shows the cross-sectional pattern which the grooves make. Each groove, indicated by the numeral 50, is shown to have rounded edges 51 at the pavement surface which are the result of the rod being pressed laterally into the cement thus pulling the cement inwardly at the edges to form said rounded portions. It will be further evident that there is no rupture of the concrete surface membrane since the natural membrane continues downwardly into each groove 50 and upwardly around each rounded comer 51. Thus salt is prevented from attacking the aggregates of the concrete.

From the foregoing, the operation and use of the present tool will be readily understood. With the holder 25 disposed at right angles to the direction of travel whereby the flexible rods 37 project rearwardly in the direction of travel, the tool 10 is dragged forwardly on and by the fabric sheet 11 which effects a steady even pull throughout the length of the holder. The fabric sheet 11 is particularly advantageous as a dragging member when fastened to the bottom of the base 26 since it prevents the leading edge of the base 26 from digging into the concrete and disrupting the upper surface thereof. As the tool 10 is dragged along, the entire width of the lane is slotted simultaneously in a single pass. Any standard road vehicle can be readily adapted for dragging the tool, and complicated machines and sensors are unnecessary. Thus, it will be seen that object of the present invention are fulfilled in the one embodiment of the invention herein disclosed.

In the following claims, the term highway includes any paved wheel supporting surface meanssuch as a vehicle roadway, street, or airport runway.

It will be understood that many changes in the details of this invention herein described and illustrated may be made without, however, departing from the spirit thereof or the scope of the appended claims.

lclaim:

l. A highway slot impressing tool for impressing slots in newly poured concrete, said tool comprising an elongated holder adapted to slide over the concrete with the longest dimension thereof disposed in a position transverse to the direction of movement of said holder; means for sliding said tool forwardly across the concrete in said transverse position whereby one elongated edge thereof represents the leading edge of said holder and the opposite elongated edge represents the trailing edge of said holder; impressing means projecting rearwardly from the trailing edge of said holder and adapted to progressively impress slots in the wet concrete; and counterweight means carried by said holder and urging said holder to rotate upwardly at said leading edge and downwardly at said trailing edge whereby said impressing means is pressed into the wet concrete.

2. A highway slot impressing tool as set forth in claim 1: said impressing means comprising a multiplicity of elongated, parallel, flexible rods projecting rearwardly and downwardly from said holder at a slight angle and pressing generally sidewise into and forming the slots.

3. A highway slot impressing tool as set forth in claim 2: said rods being substantially /8 inch in diameter and made of plastic.

4. A highway slot impressing tool as set forth in claim 2: said counterweight means comprising supports projecting upwardly and rearwardly above said rods; counterweights carried by said supports for biasing said rods downwardly.

5. A highway slot impressing tool as set forth in claim 4: said counterweights being adjustable rearwardly and forwardly with respect to said support to adjust the lever arm between said holder and counterweight and vary the downward pressure on said rods.

6. A highway slot impressing tool as set forth in claim 5: each said support comprising an upright member mounted in and projecting upwardly from said holder; a rearwardly cantilevered, threaded bolt fixed adjacent to the upper end portion of said upright member; said counterweight being internally threaded whereby said counterweight is rotatably movable forwardly and rearwardly to adjust said lever arm.

7. A highway slot impressing tool as set forth in claim 2: said holder including means releasably retaining said flexible rods.

8. A highway slot impressing tool as set forth in claim 2: said holder comprising an elongated base having a horizontal lip projecting rearwardly adjacent to the lower surface of said base; said base having an upwardly projecting step adjacent to the forward end of said lip; said lip having a rearwardly downwardly slanting upper surface; said rods having forwardly directed ends disposed on said upper surface; said holder comprising an elongated clamping portion overlying said lip and having a lower surface slanting rearwardly and downwardly at the same angle as the upper surface of said lip; and means for tightening said clamping portion with respect to said base whereby said rods are clamped between said slanting surfaces.

9. A highway slot impressing tool as set forth in claim 8: said means for tightening said clamping portion comprising bolt means extending horizontally through said clamping portion and the step of said base whereby said clamping means is tightened in the direction of said step to bring said slanting surfaces together to clamp said rods.

10. a highway slot impressing tool as set forth in claim 9: said clamping portion having parallel, spaced grooves disposed in said lower surface perpendicular to the longitudinal dimension of said clamping portion, each forwardly directed rod end being disposed in one of said grooves.

11. A highway slot impressing tool as set forth in claim 9: one of said slanting surface portions having means defining parallel, spaced grooves therein disposed perpendicular to the longitudinal dimension of said holder, each forwardly directed rod end being disposed in one of said grooves.

2. A highway slot impressing tool as set forth in claim 9: means fixed with respect to said base and projecting rearwardly above and closely overlying said clamping portion to limit upwardly movement of said clamping portion when said bolt means is tightened.

13. A highway slot impressing tool as set forth in claim 1: said means for sliding said tool comprising a sheet of fabric material extending substantially the length of said holder; means securing a rearwardly directed edge portion of said sheet to the bottom of said base; said tool adapted to be dragged across the concrete by pulling on a forwardly directed edge of said sheet.

14. A highway slot impressing tool as set forth in claim 13: pulling means for dragging said tool including a transverse, forwardly movable boom spaced above the surface of said concrete.

15. A highway slot impressing tool for impressing parallel slots in newly poured concrete, said tool comprising an elongated holder adapted to slide over the concrete with the longest dimension thereof disposed transverse to the direction of movement of said holder, one elongated edge of said holder being the leading edge and the opposite elongated edge being the trailing edge; a multiplicity of elongated, flexible rods evenly spaced along said holder and projecting rearwardly and slightly downwardly from said trailing edge, said rods pressing sideways into the wet concrete and progressively forming slots therein; a plurality of counterweight supports projecting upwardly at spaced intervals along said holder and having means projecting substantially rearwardly generally above said rods; and counterweights mounted for adjustable movement along said rearwardly projecting means to exert varying downward pressure upon said rods. 

1. A highway slot impressing tool for impressing slots in newly poured concrete, said tool comprising an elongated holder adapted to slide over the concrete with the longest dimension thereof disposed in a position transverse to the direction of movement of said holder; means for sliding said tool forwardly across the concrete in said transverse position whereby one elongated edge thereof represents the leading edge of said holder and the opposite elongated edge represents the trailing edge of said holder; impressing means projecting rearwardly from the trailing edge of said holder and adapted to progressively impress slots in the wet concrete; and counterweight means carried by said holder and urging said holder to rotate upwardly at said leading edge and downwardly at said trailing edge whereby said impressing means is pressed into the wet concrete.
 2. A highway slot impressing tool as set forth in claim 1: said impressing means comprising a multiplicity of elongated, parallel, flexible rods projecting rearwardly and downwardly from said holder at a slight angle and pressing generally sidewise into and forming the slots.
 3. A highway slot impressing tool as set forth in claim 2: said rods being substantially 1/8 inch in diameter and made of plastic.
 4. A highway slot impressing tool as set forth in claim 2: said counterweight means comprising supports projecting upwardly and rearwardly above said rods; counterweights carried by said supports for biasing said rods downwardly.
 5. A highway slot impressing tool as set forth in claim 4: said counterweights being adjustable rearwardly and forwardly with respect to said support to adjust the lever arm between said holder and counterweight and vary the downward pressure on said rods.
 6. A highway slot impressing tool as set forth in claim 5: each said support comprising an upright member mounted in and projecting upwardly from said holder; a rearwardly cantilevered, threaded bolt fixed adjacent to the upper end portion of said upright member; said counterweight being internally threaded whereby said counterweight is rotataBly movable forwardly and rearwardly to adjust said lever arm.
 7. A highway slot impressing tool as set forth in claim 2: said holder including means releasably retaining said flexible rods.
 8. A highway slot impressing tool as set forth in claim 2: said holder comprising an elongated base having a horizontal lip projecting rearwardly adjacent to the lower surface of said base; said base having an upwardly projecting step adjacent to the forward end of said lip; said lip having a rearwardly downwardly slanting upper surface; said rods having forwardly directed ends disposed on said upper surface; said holder comprising an elongated clamping portion overlying said lip and having a lower surface slanting rearwardly and downwardly at the same angle as the upper surface of said lip; and means for tightening said clamping portion with respect to said base whereby said rods are clamped between said slanting surfaces.
 9. A highway slot impressing tool as set forth in claim 8: said means for tightening said clamping portion comprising bolt means extending horizontally through said clamping portion and the step of said base whereby said clamping means is tightened in the direction of said step to bring said slanting surfaces together to clamp said rods.
 10. a highway slot impressing tool as set forth in claim 9: said clamping portion having parallel, spaced grooves disposed in said lower surface perpendicular to the longitudinal dimension of said clamping portion, each forwardly directed rod end being disposed in one of said grooves.
 11. A highway slot impressing tool as set forth in claim 9: one of said slanting surface portions having means defining parallel, spaced grooves therein disposed perpendicular to the longitudinal dimension of said holder, each forwardly directed rod end being disposed in one of said grooves.
 12. A highway slot impressing tool as set forth in claim 9: means fixed with respect to said base and projecting rearwardly above and closely overlying said clamping portion to limit upwardly movement of said clamping portion when said bolt means is tightened.
 13. A highway slot impressing tool as set forth in claim 1: said means for sliding said tool comprising a sheet of fabric material extending substantially the length of said holder; means securing a rearwardly directed edge portion of said sheet to the bottom of said base; said tool adapted to be dragged across the concrete by pulling on a forwardly directed edge of said sheet.
 14. A highway slot impressing tool as set forth in claim 13: pulling means for dragging said tool including a transverse, forwardly movable boom spaced above the surface of said concrete.
 15. A highway slot impressing tool for impressing parallel slots in newly poured concrete, said tool comprising an elongated holder adapted to slide over the concrete with the longest dimension thereof disposed transverse to the direction of movement of said holder, one elongated edge of said holder being the leading edge and the opposite elongated edge being the trailing edge; a multiplicity of elongated, flexible rods evenly spaced along said holder and projecting rearwardly and slightly downwardly from said trailing edge, said rods pressing sideways into the wet concrete and progressively forming slots therein; a plurality of counterweight supports projecting upwardly at spaced intervals along said holder and having means projecting substantially rearwardly generally above said rods; and counterweights mounted for adjustable movement along said rearwardly projecting means to exert varying downward pressure upon said rods. 